The present invention relates generally to processes and devices for preparing film strips for subsequent orders.
In the photo finishing industry, customers typically get back their developed negative films cut in strips instead of in single pieces. These film strips normally contain 4 to 6 negative images. If the customer intends to subsequently order further pictures at a later date, he selects the corresponding negative from the first order with the help of the already existing paper image. Depending on the manner in which the negative film strips are presented, there are different ways for the customer to inform the photo lab which negative on the respective film strip is to be used to prepare paper images, and how many paper images are to be prepared.
With film strips having a paper strip, known as a "tab strip", glued along their longitudinal edge, the customer can mark on the paper strip under the respective negative the number of copies and, where necessary, the desired picture format.
If the customer gets the cut film strips back without glued tab strips, a table containing all negative numbers is often printed on the packaging of the film strips or on the order bag. The customer or the operating personnel in the photo shop then reads the corresponding negative number on the film strip and records on the table the desired number of copies and, where necessary, the image format as well.
With some first processing runs of customer orders, the negative numbers can also be already printed on the reverse of the specific related picture. In this case, the customer simply reads the corresponding number from the reverse of the picture and records this number and, where necessary, the desired image format on a table on the order bag. The customer no longer has to look through the cut film strips for the negatives he wants, but rather he places all related film strips of a first-order into the order bag.
The order bag provided with the customer's address is finally delivered to the photo lab. So that the various subsequent orders can be processed rationally in a large photo finishing lab, the individual cut film strips from several orders are usually glued to a carrier belt in a preparation station and coiled into a film roll. In the process, the order data are also detected, entered into the preparation station and transferred onto a data carrier, for example a computer diskette or the like. The film roll and the data carrier are then passed on to a further processing station, for example a photographic printer, in which the orders are preferably processed fully automatically and the desired photographic copy-prints are produced. There are usually two methods for entering the order data of an order, depending on the type of customer order.
With film strips with glued-on tab strips, the customer must record his selections below the corresponding negative on the strip. The operating personnel at the preparation station reads the customer details from the tab strip of the respective film strip and enters these data via a keyboard into the preparation station either before or after introducing the film strip.
In cases where the order-specific customer data are contained in a table that is printed on the order bag or on other packaging elements of the film strips, the operating personnel selects what is known as a table mode at the preparation station and enters the customer details contained in the table via a keyboard into the preparation station. In the process, what is known as a device table is prepared inside the apparatus; it essentially represents an electronic copy of the table filled out by the customer. After this, the operating personnel inserts the cut film strips individually in random order into the preparation station, where they are glued to a carrier belt in a further sequence. To guarantee that the negatives on the inserted film strip are properly correlated with the customer data on the device table, the operating personnel must always inform the preparation station of the respective first negative number of the inserted film strip as well. In addition, the operating personnel must make sure that the film strips are always inserted in the same manner, i.e., the emulsion side of the film strips must be in the proper position (usually facing down), and a once selected type of negative number sequence, ascending or descending, must be maintained.
When inserting the cut film strips into the preparation station, where they are glued to a carrier belt and coiled into a film roll, one must often watch out for a number of faulty manipulations which can negatively affect the work process and especially the processing time of a customer order. It can occur that a film strip is inserted slightly crooked and is glued to the carrier belt in this position. Besides the fact that this can lead to disturbances in the guiding of the film material in subsequent fully automatic processing stations, pictures with unattractive edges are often produced in this way. Such pictures are unacceptable for the customer as a rule, and the copying process must be repeated with properly positioned film strips. It also occurs that film strips are inserted with the emulsion layer on the wrong side and are glued to the carrier belt in this position. This later leads to laterally reversed, blurred images which are equally unacceptable and result in repeating the entire process. Especially with images containing motifs and lettering, the writing is portrayed reversed in this case, which is of course completely unacceptable.
Often, film strips are also inserted that do not contain any negatives of which the customer wants a print. This is especially the case when the customer sends all film strips along with the print order. In this way, many film strips are unnecessarily glued to the carrier belt, and this can lead to massive productivity losses in the preparation station and much more so at the subsequent automatic processing stations.
With the known preparation stations, the elimination of all of these errors is only possible after the film strips are glued on. Provided the error is ascertained at all, the operating personnel can indicate to the apparatus that a film strip is to be removed. This procedure is relatively costly, however, since in this case, the already glued-on film strip must be detached from the carrier belt again and, where necessary, inserted anew. In the process, on the film roll glued together from individual film strips, a gap is created in the carrier belt, which can lead to disturbances in further processing in the subsequent, typically fully automatic stations. In addition, the preparation station is stopped while the error is being eliminated.
A process and a device for preparing film strips for subsequent orders is therefore desirable in which the aforementioned operating errors and superfluous insertions of unneeded film strips are compensated to the effect that no productivity losses occur. Disturbances and faulty exposures due to faulty positions of film strips should be avoided.